301 thrift store find

[Vox T]

Thanks guys The Garrard was good before but now it is in another league. It has far exceeded my expectations for what 1955 vintage turntable could do. Simply amazing. ]

It's not really a 1955 turntable though is it? Modern tonearm, modern cartridge etc. Basically the motor and platter is vintage and that's about the extent of it. Like installing a 1966 V12 Jaguar engine into a 2010 Lexus chassis.

[josephazannieri]

Yo Iain:

Glad to hear that it's progressing. There are a couple of ways to slow it down. You could just have somebody chuck that motor pulley into a lathe and shave it a little. Just a hundredth of a hair or less at a time, until you get it to turn at the right speed with the speed control centered. You will need to measure the speed by counting the number of turns over time. This is much more accurate than trying to measure by the number of turns in a minute or using a strobe, because most strobes don't give percentage fast or slow. I have a PDF one that I will send if you want, but it only shows 2 or 4 percent fast or slow. You could count the number of turns in 3 minutes because 33 1/3 times 3 is a nice even 100 revolutions. You could measure the length of time it takes you to do 200 or 300 revs with a digital stopwatch and see what that gives you for speed.

Once you know percentage fast or slow, you can measure the circumference of the motor pulley (C = pi times d) and use the percentage to determine exactly how much to shave off diameter. You will need a micrometer or digital calipers. It's change of C that determines the change of speed. I would be real careful and have a machinist do it. You don't want to cut too much. There is probably a job machine shop that could help if you put the problem to the craftsman (or woman) there.

Then there is also the quick'n'dirty way, which is to throw the TT on a Variac and cut the voltage till it comes to speed. Make sure that the speed control is centered when you set voltage. Some guys say that when you start cutting voltage, you lose some of the rhythmic strength of the Garrard because you cut motor power, and the thing that makes that 301 drive so hard is the fact that the motor is so strong. Using the brake reduces the voltage change required to get to speed.

For what it's worth, I have had high compliance carts in relatively massive arms, with good results. I am not quite as concerned with the theoretical ideal as some are, because of the flexibility of cartridge compliance measurements, and the GIGO aspect of the theoretical formulas. Currently running an ADC QLM 36/III (1.2 G) on a stock Lenco L75 and it works fine. Traded it for a B&O SP-14 (2-3G), thinking it would help, and the B&O really stunk and I went back. That's for what it's worth. For me, if it sounds good, it is a success, regardless of theory. But there might be a benefit in going to a good MC.

That's another too-long post. Hope you survived it. Glad to hear of progress! Your continued attention to correspondence keeps the readers interested. Good luck from the crude, chatty old guy,

Joe Z.

[iain42]

Yo Iain:

Glad to hear that it's progressing. There are a couple of ways to slow it down. You could just have somebody chuck that motor pulley into a lathe and shave it a little. Just a hundredth of a hair or less at a time, until you get it to turn at the right speed with the speed control centered. You will need to measure the speed by counting the number of turns over time. This is much more accurate than trying to measure by the number of turns in a minute or using a strobe, because most strobes don't give percentage fast or slow. I have a PDF one that I will send if you want, but it only shows 2 or 4 percent fast or slow. You could count the number of turns in 3 minutes because 33 1/3 times 3 is a nice even 100 revolutions. You could measure the length of time it takes you to do 200 or 300 revs with a digital stopwatch and see what that gives you for speed.

I think it is about 35 instead of 33 1/3. This was consistent. I'll let it warm up good and measure again. Please send the PDF.

Once you know percentage fast or slow, you can measure the circumference of the motor pulley (C = pi times d) and use the percentage to determine exactly how much to shave off diameter. You will need a micrometer or digital calipers. It's change of C that determines the change of speed. I would be real careful and have a machinist do it. You don't want to cut too much. There is probably a job machine shop that could help if you put the problem to the craftsman (or woman) there.

Bloody hell man you know I'm low tech ROFLMAO. Calipers micrometer wth : ) I'll ask some of my smart friends to see if they have any of these tools. I don't mind buying an extra pulling just in case.

Then there is also the quick'n'dirty way, which is to throw the TT on a Variac and cut the voltage till it comes to speed. Make sure that the speed control is centered when you set voltage. Some guys say that when you start cutting voltage, you lose some of the rhythmic strength of the Garrard because you cut motor power, and the thing that makes that 301 drive so hard is the fact that the motor is so strong. Using the brake reduces the voltage change required to get to speed.

This makes sense. I have a variac but I'd rather not fix it that way.

For what it's worth, I have had high compliance carts in relatively massive arms, with good results. I am not quite as concerned with the theoretical ideal as some are, because of the flexibility of cartridge compliance measurements, and the GIGO aspect of the theoretical formulas. Currently running an ADC QLM 36/III (1.2 G) on a stock Lenco L75 and it works fine. Traded it for a B&O SP-14 (2-3G), thinking it would help, and the B&O really stunk and I went back. That's for what it's worth. For me, if it sounds good, it is a success, regardless of theory. But there might be a benefit in going to a good MC.

I'll try the theoretical ideal for the experience. I'd like to try an MC cart anyway. It will be interesting to compare.

That's another too-long post. Hope you survived it. Glad to hear of progress! Your continued attention to correspondence keeps the readers interested. Good luck from the crude, chatty old guy,

Joe Z.

Thanks again for the help and information.

[Blue Angel]

Hi Iain

I looked yesterday for the speed issue? but couldn't find any reference to it? If it's running too fast, can you substitute the bearing oil with something of a lower viscosity?

blue angel

[iain42]

Hi Iain

I looked yesterday for the speed issue? but couldn't find any reference to it? If it's running too fast, can you substitute the bearing oil with something of a lower viscosity?

blue angel

I guess I could also try that before going to a machinists.

This is what I am currently using. What viscosity do you think I should try next?


It is very cool that I have a couple options.

[josephazannieri]

Yo Blue and Iain:

I remember way back when. I think Blue advised Iain to use that 85-90 weight gear oil in that spindle bearing, and Iain used that Coastal stuff.

On oil I would look at a couple of things, with a question for Blue. It might be worth your while to get gear oil at a tractor shop. That car gear oil sometimes has molybdenum (?) as an additive, which makes it a little more slippery than oil without the additive. Tractor gear oil sometimes does not have the additives. I would look for an oil that had no additives that increased slipperyness.

Blue suggests lower viscosity (thinner) oil as a way to increase the drag in that center bearing to slow the TT down. I thought it would take higher viscosity (thicker) oil to achieve this objective. Perhaps he could explain. If it were I, I would get rid of the oil and use wheel bearing grease instead. But maybe that's a nono.

Good luck from the oily old greaser!

Joe Z.

[gortnipper]

Iaian - Perfect Sound also has pulleys sized slightly smaller to slow your table down. I have ordered one from Steve for my 301 since I just never could get it in to a machinist to do the little at a time thing. They are the same price as the normal ones in their ebay sgtore - http://cgi.ebay.com/British-Made-Garrar ... _644wt_939

Steve also may have new idler wheels now, or very soon - you should ask him about it.

David

Still no BRG plinth but it is very close.

I've been buying loads of vinyl and playing lots of tunes while my brother finishes my plinth. Hopefully next month . I've also sweetened the deal so he will paint it for me as well or this might never finish.

A couple of changes to be made before it arrives. It seems the cartridge I purchased is not optimal. I've been reading about arm mass and cart compliance which has helped. A member of another forum showed me some spreadsheet and how to use it. It seems on paper the Denon DL-110 is a good match for the Jelco high mass arm. This is great as it is an affordable mc and can be run off of my current phono preamp.

Arm Mass 26 Cartridge Mass 4.8 Compliance 8 Resonance Frequency 10.12

The cartridge database mentions this about the denon 110
*Denon publishes their dynamic compliance specifications relative to 100Hz . The actual compliance at 10Hz will be higher.

Would this cartridge still be acceptable?


I have ordered a spring replacement package from perfect sound. I was going to order a replacement idler wheel but can't find one for sale. Does any know who sells them? The current on is over 50 years old so why not put on a new one.

The table is also running a little fast after the bearing relube. I tried adding magnets to the magnetic break but that did not help. Even if the magnetic break is full on it doesn't slow it down enough. Any advice on this is much appreciated. I'm sure this won't be too hard to resolve. At least it is too fast and not too slow.

As always if I got anything wrong or backwards please let me know.

[gortnipper]

Iain - Perfect Sound also has pulleys sized slightly smaller to slow your table down. I have ordered one from Steve for my 301 since I just never could get it in to a machinist to do the little at a time thing. They are the same price as the normal ones in their ebay store - http://cgi.ebay.com/British-Made-Garrar ... _644wt_939

Steve also may have new idler wheels now, or very soon - you should ask him about it.

David

Still no BRG plinth but it is very close.

I've been buying loads of vinyl and playing lots of tunes while my brother finishes my plinth. Hopefully next month . I've also sweetened the deal so he will paint it for me as well or this might never finish.

A couple of changes to be made before it arrives. It seems the cartridge I purchased is not optimal. I've been reading about arm mass and cart compliance which has helped. A member of another forum showed me some spreadsheet and how to use it. It seems on paper the Denon DL-110 is a good match for the Jelco high mass arm. This is great as it is an affordable mc and can be run off of my current phono preamp.

Arm Mass 26 Cartridge Mass 4.8 Compliance 8 Resonance Frequency 10.12

The cartridge database mentions this about the denon 110
*Denon publishes their dynamic compliance specifications relative to 100Hz . The actual compliance at 10Hz will be higher.

Would this cartridge still be acceptable?


I have ordered a spring replacement package from perfect sound. I was going to order a replacement idler wheel but can't find one for sale. Does any know who sells them? The current on is over 50 years old so why not put on a new one.

The table is also running a little fast after the bearing relube. I tried adding magnets to the magnetic break but that did not help. Even if the magnetic break is full on it doesn't slow it down enough. Any advice on this is much appreciated. I'm sure this won't be too hard to resolve. At least it is too fast and not too slow.

As always if I got anything wrong or backwards please let me know.

[josephazannieri]

Yo Iain:

Your oil is a multigrade (90W-140) which increases in viscosity (gets thicker) as temp gets higher and decreases in viscosity (gets thinner) as temp gets lower. Maybe a single-grade 90 weight from a tractor store?

Still oily and greasy,

Joe Z.

[iain42]

Thanks guys.

I'm going to the tractor supply store tomorrow. There is a Tractor Supply store in town. That cracks me up.

I printed the strobe disks and they work well. I'll try some thicker oils. If it is still fast I'll pick up a pulley and have it machined a little.

I ordered the springs from perfect sound so I'll send him an email regarding idler wheel and pulley.

This should be interesting.

[Blue Angel]

Thanks guys.

I'm going to the tractor supply store tomorrow. There is a Tractor Supply store in town. That cracks me up.

I printed the strobe disks and they work well. I'll try some thicker oils. If it is still fast I'll pick up a pulley and have it machined a little.

I ordered the springs from perfect sound so I'll send him an email regarding idler wheel and pulley.

This should be interesting.

Haha,

Who was it who called 301's 'agricultural'?

Sorry about my slip-up It was late at night. I meant a higher viscosity.

The oil you are using has the same rating as mine, except for the brand which is Castrol at my end.

I wouldn't easily get a machinist to turn down a pulley as mistakes can easily occur and changes are irreversible. I would experiment with thicker oil or even a small, powerful neodymium magnet placed near the eddy assembly's magnet - something like 10x10x5mm

blue angel

[iain42]

Thanks guys.

I'm going to the tractor supply store tomorrow. There is a Tractor Supply store in town. That cracks me up.

I printed the strobe disks and they work well. I'll try some thicker oils. If it is still fast I'll pick up a pulley and have it machined a little.

I ordered the springs from perfect sound so I'll send him an email regarding idler wheel and pulley.

This should be interesting.

Haha,

Who was it who called 301's 'agricultural'?

Sorry about my slip-up It was late at night. I meant a higher viscosity.

The oil you are using has the same rating as mine, except for the brand which is Castrol at my end.

I wouldn't easily get a machinist to turn down a pulley as mistakes can easily occur and changes are irreversible. I would experiment with thicker oil or even a small, powerful neodymium magnet placed near the eddy assembly's magnet - something like 10x10x5mm

blue angel

Somehow I still knew what you meant.

I bought some small magnets at Home Depot but they didn't make much a change. That being said I am not sure what kind of magnets they were. I'll check next time I am at the store. I'll also look for some neodymium magnets. The combo of thicker oil and magnets could do the trick.However if I am still fast I'll buy another pulley and let the machinists have a whack at it. That way I'll still have the original.



Without much of a warm up my table was %4 fast with the speed control in the middle. I'm going to spin records tonight and this weekend. I'll check speed again after it has spun records for a few hours.

EDIT:
Oddly enough tractor supply did not have anything heavier than what I already have.

I did order a selection of neodynium magnets in varying pull strengths from 23lbs to 135lbs. They are small : ) Should be interesting.

[iain42]

Ok I finally found 90 single weight oil. I have gone from 4% fast to 2% fast. I'll let the oil settle then I'll take another measurement tomorrow. That is an improvement and I'll take it. If I can find 95 weight oil I wonder if that would get me the rest of the way home The guys at the tractor store said I might try oil stabilizer. I'm not sure about that but I am looking into it. It seems like that makes it slicker with the extra additives.

[josephazannieri]

Yo Iain:

If you are now 2% fast with the speed control centered, you should be able to get the right speed with the speed control. Mine goes from about +3% to about -4% with the speed control nailed either way.

Maybe Blue is right and a more intense magnet would help, too. Those Alnico magnets do lose strength over time, or so I hear. and yours is about 45 years old, as opposed to mine, which is about 10 years older. But my speed control seems OK, since it gives right speed with control centered.

I think when they say "oil stabilizer" they are talking about STP or some goo like that. There is a patented chemical that makes the oil sticky and helps it adhere to the various things it lubricates. Next time I am at the parts store, I will see if the display is still there and get the brand name. I will have to reline the brakes on my pickup in the next couple of weeks after the weather breaks. The wear sensors have started to sing like crazy.

Good luck from the half-fast old mechanic! (not real slow, not real quick- just half-fast)

Joe Z.